Method of adjusting a height of a car floor plane of a railroad car and height adjustment system

ABSTRACT

There is provided a method of adjusting a height of a car floor plane of a railroad car relative to a platform of a train station. The method includes, using a height adjusting system mounted to an exterior side of the railroad car adjacent the car floor plane, emitting a first ultrasonic beam towards the platform of the train station and monitoring a reflection of the first ultrasonic beam; and generating a first signal based on said monitoring the reflection of the first ultrasonic beam. The method includes, using a processor, operating an actuator of a suspension system of the railroad car to adjust the height of the car floor plane to a height of the platform of the train station based on the generated first signal.

FIELD

The improvements generally relate to the field of railroad cars and more particularly relate to height adjustment systems of such railroad cars.

BACKGROUND

A typical train generally has a series of railroad cars moved as a whole along a railroad. Each railroad car generally has a car body and trucks (i.e. chassis underneath the car body to which wheel axles and wheels are attached through bearings) movably mounted to the car body via a suspension system allowing raising and lowering of a height of a car floor plane of the car body.

When the train travels from one train station to another, the suspension system of each railroad car is generally actuated to raise the car floor plane of the car body to a given height relative to the rail. For example, the TS 11.03 H and 2.01.L standards, where applicable, specify that the given height ranges between 43.5 inches and 45.5 inches depending on passenger loading. On platforms affected by these standards, the typical train station generally has a nominal platform height of 42.25 inches relative to the rail. This implies that, when the train arrives at the train station, the car floor plane of each railroad car has to be lowered of about 1.25-3.25 inches in order for the height of the car floor plane to coincide with the nominal platform height. As can be understood, the amount of vertical distance that the car floor plane has to be lowered at each arrival can vary from one station to another and/or from one passenger load to another.

Correspondence between the height of the car floor plane and the nominal platform height of a train station is of importance as any vertical gap therebetween can be inconvenient. Consequently, some existing railroad cars are equipped with distance detection systems configured to match the height of the car floor plane with the nominal platform height. For instance, one existing distance detection system is configured to monitor a vertical distance between a reference point associated to the car body and a reference point associated to the trucks. When the train arrives at the train station, the suspension system is actuated to lower the car floor plane such that the monitored vertical distance reaches a reference vertical distance which is predetermined so that the height of the car floor plane is expected to correspond to the nominal platform height.

Although existing distance detection systems were satisfactory to a certain degree, there remains room for improvement, particularly when the nominal platform height varies from one train station to another and when the actual height of the platform varies due to temperature change.

SUMMARY

It was found that because the existing distance detection systems are configured to detect the vertical distance between the car body and the trucks, an unsatisfactory vertical gap can be created between the car floor plane and the platform when the actual height of the platform deviates from the nominal platform height.

Therefore, there is provided a method of adjusting a height of the car floor plane based on an actual height of the platform of the train station. In this method, an ultrasonic beam is emitted from an exterior side of the railroad car adjacent to the platform and in direction of the platform while a reflection of the ultrasonic beam is monitored. Accordingly, the height of the car floor plane can be adjusted such that the height of the car floor plane corresponds, within a given threshold height value, to the actual height of the platform of the train station based on the monitored reflection of the ultrasonic beam.

The method can be performed using a height adjustment system including a housing with a back face connectable to the exterior side of the car body and an opposite front face where a first ultrasonic sensor is provided. When the height adjustment system is mounted to the exterior side of the car body, the first ultrasonic sensor faces away from the car body and towards the platform. In some embodiments, the height adjustment system can have a second “safety” ultrasonic sensor facing away from the car body and towards the platform but at a vertical position different from the vertical position of the first ultrasonic sensor.

In accordance with one aspect, there is provided a method of adjusting a height of a car floor plane of a railroad car relative to a platform of a train station, the method comprising: using a height adjusting system mounted to an exterior side of the railroad car adjacent the car floor plane, emitting a first ultrasonic beam towards the platform of the train station and monitoring a reflection of the first ultrasonic beam; generating a first signal based on said monitoring the reflection of the first ultrasonic beam; and using a processor, operating an actuator of a suspension system of the railroad car to adjust the height of the car floor plane to a height of the platform of the train station based on the generated first signal.

In accordance with another aspect, there is provided a height adjustment system to be mounted to an exterior side of a car body of a railroad car, the height adjustment system comprising: a housing having a back face being removably mountable to the exterior side of the car body and an opposite front face; at least one ultrasonic sensor mounted to the front face of the housing, the at least one ultrasonic sensor being configured to emit an ultrasonic beam away from the front face of the housing and outwardly from the car body when the housing is mounted to the exterior side of the car body; and at least one electrical connector mounted to the back face of the housing and electrically connected to the at least one ultrasonic sensor.

In accordance with another aspect, there is provided a method of adjusting a height of a car floor plane of a railroad car relative to a platform of a train station, the method comprising: using a height adjusting system mounted to an exterior side of the railroad car adjacent the car floor plane, emitting a first ultrasonic signal towards the platform of the train station; and monitoring a reflection of the first ultrasonic signal against the platform, including generating an electromagnetic signal indicative of whether or not the reflection is detected; and using a processor to receive the electromagnetic signal and operate an actuator of a suspension system of the railroad car to adjust the height of the car floor plane based on the electromagnetic signal received.

Many further features and combinations thereof concerning the present improvements will appear to those skilled in the art following a reading of the instant disclosure.

DESCRIPTION OF THE FIGURES

In the figures,

FIG. 1 is a front elevation view of an example of a railroad car having a car body wherein the car body has height adjustment systems on each exterior side thereof, exemplary of an embodiment;

FIG. 1A is an enlarged view of a portion of FIG. 1, exemplary of an embodiment;

FIG. 2 is a side elevation view of the railroad car of FIG. 1, showing two height adjustment systems on a same exterior side of the car body, exemplary of an embodiment;

FIGS. 3 and 4 are cross sectional views of the railroad car of FIG. 1, showing a car floor plane of the car body at two different heights relative to a platform of a train station; and

FIG. 5 is a schematic view of an example of a height adjustment system, exemplary of an embodiment.

DETAILED DESCRIPTION

FIGS. 1 and 2 show an example of a railroad car 10. As depicted, the railroad car 10 has a car body 12, a frame 13 supporting the car body 12, and trucks 14 mounted to the frame 13 via a suspension system 16. An enlarged view of the suspension system 16 is shown in FIG. 1A wherein the suspension system 16 is shown with an actuator 15 and suspension springs 19. In this embodiment, the actuator 15 includes one or more hydraulic cylinders 17 which can be operated by one or more processors (referred to as the “processor 18”) to lower or raise the height of the car body 12 relative to the railroad during use. The processor 18 is in communication with the actuator 15 to control the height at which the car body 12 is adjusted.

For ease of understanding, the car body 12 can be lowered when the actuator 15 is operated, e.g., by the processor 18, to compress the suspension springs 19 of the suspension system 16. Conversely, the car body 12 can be raised when the actuator is operated, e.g., by the processor 18, to relieve the tension in the suspension springs 19.

In the specific embodiment shown, two height adjustment systems 20 are provided on each exterior side of the car body 12, adjacent to a car floor plane 22 of the car body 12, for a total of four height adjustment systems 20. However, in some other embodiments, there can be a single height adjustment system provided on either or both of the exterior sides of the car body 12.

Each height adjustment system 20 is in wired or wireless communication with the processor 18 such that, upon reception of instructions to adjust the height of the car floor plane 22, the processor 18 can operate the actuator 15 of the suspension system 16 to lower the car floor plane 22 of the car body 12 based on feedback of one or more of the height adjustment systems 20. Such instructions can follow the reception of an “open command” associated with the opening of a door of one of the exterior sides of the car body 12 and from the detection that the railroad car 10 has a speed of less than 3 mph, for instance. Such an “open command” can be transmitted when a railroad engineer, for instance, pushes a button.

Referring now to FIGS. 3 and 4, there is described a method for adjusting a height of the car floor plane 22 when the railroad car is adjacent to a platform 30. For instance, the method can be performed when it is detected that the railroad car arrives at a train station or while the railroad car waits with opened doors at a train station.

As mentioned above, each height adjustment system 20 is mounted to the exterior of the car body 12 and faces away from the car body and towards the platform 30. As can be seen, the height adjustment system 20 has a first ultrasonic sensor 32 configured to emit a first ultrasonic beam 34 outwardly from the car body 12 and towards the platform 30. In the embodiment shown, the first ultrasonic beam 34 is emitted horizontally along the car floor plane 22. The height adjustment system 20 can have a second ultrasonic sensor 38 (e.g., a safety sensor) above the first ultrasonic sensor 32 which, when activated, can propagate a second ultrasonic beam 40 outwardly from the car body 12 towards the platform 30. Each of the first and second ultrasonic sensors 32 and 38 is configured to monitor a reflection of a respective one of the first and second ultrasonic beams 34 and 40 and to generate a signal indicative of the monitored reflection. In some embodiments, the signal can be indicative of an intensity of the monitored reflection. In some other embodiments, the signal can be indicative of a distance between the ultrasonic sensor and an object that appears in a line of sight of the ultrasonic sensor.

Accordingly, the first ultrasonic sensor 32 is configured to generate a first signal which is indicative of the reflection of the first ultrasonic beam 34. In some embodiments, the processor 18 is configured to adjust the height of the car floor plane 22 based on the first signal. In some embodiments, the first signal is indicative of a first distance value corresponding to the distance between the first ultrasonic sensor 32 and an object that appears in a line of sight of the first ultrasonic sensor 32, such as the platform 30. The distance can be measured horizontally in some embodiments. In some embodiments, the first distance value can be determined based on the intensity of the monitored reflection. However, in some other embodiments, where the first ultrasonic beam 34 is an ultrasonic pulsed beam, the first distance value can be determined based on time delays and/or phase shifts between emitted ultrasonic pulses and their respective reflections such as in ultrasonic ranging systems. As will be described below, the height adjustment of the car floor plane 22 can be based on a comparison of the first distance value with a threshold value.

Similarly, the second ultrasonic sensor 38 is configured to generate a second signal which is indicative of the reflection of the second ultrasonic beam 40. The second signal can be indicative of a second distance value corresponding to the distance between the second ultrasonic sensor 38 and an object such as the platform 30. In embodiments where a second ultrasonic sensor 38 is provided, the processor 18 is configured to adjust the height of the car floor plane 22 based on the first and second signals. However, the second ultrasonic sensor 38 is optional.

In some embodiments, when it is determined that the “open command” is activated and that the railroad car 10 has a speed lower than 3 mph, the processor 18 monitors a first distance value measured using the first ultrasonic sensor 32 that emits the first ultrasonic beam 34 towards the platform 30. At this stage, if the monitored first distance value is greater than an expected distance threshold value 37, it can be deducted that the first ultrasonic beam 34 is propagated above a top edge 36 of the platform 30 and therefore the processor 18 maintains operation of the actuator 15 of the suspension system 16 to lower the car floor plane 22 further below, as shown in FIG. 3. In the embodiment shown, the expected distance threshold value 37 is representative of the expected distance between the car body 10 and the platform 30. As the car floor plane 22 is being lowered, the processor 18 continuously monitors the first distance value and compares it with the expected distance threshold value 37. Once it is determined that the first distance value is equal or smaller than the expected distance threshold value 37, such as shown in FIG. 4, the processor 18 stops to operate the actuator 15 of the suspension system 16 which stops the lowering of the car floor plane 22.

The height of the car floor plane 22 can remain constant over time unless there is a leak in the hydraulic cylinder(s) 17, for instance. Nonetheless, the processor 18 continues to monitor the first distance value until the “open command” disappears (or upon reception of a “close command”). In some embodiments, when it is determined that the first distance value increases above the expected distance threshold value 37 while an “open command” is activated, it can mean that the height of the car floor level 22 has increased and therefore the processor 18 operates the actuator 15 to lower the car floor plane 22 until the first distance value is equal or smaller than the expected distance threshold value 37 again.

Simultaneously to monitoring of the first distance value, the processor 18 can also monitor the second distance value measured using the second ultrasonic sensor 38. When the height of the car floor plane 22 substantially corresponds to the height of the platform 30, the second distance value is generally greater than the expected distance threshold value 37. If it is determined that the second distance value is equal or smaller than the expected distance threshold value 37, it can mean that the height of the car floor plane 22 is lower than it should be. Consequently, in this situation, the processor 18 can operate the actuator 15 of the suspension system 16 to raise the car floor plane 22 until the second distance value is greater than the expected distance threshold value 37 again.

It is understood that, for a vertical gap between the height of the car floor plane 22 and the height of the platform 30 to be acceptable, the height of the car floor plane 22 can be adjusted to be within a given threshold height value relative to the height of the platform 30. An example of such a threshold value is ⅜ of an inch, which has been found to be satisfactory in some embodiments. In the specific embodiment shown, the first ultrasonic beam 34 is emitted along a first beam path 24 which is parallel to and below the car floor plane 22 by a first vertical offset. An example of a first vertical offset between the first beam path 24 and the car floor plane 22 is an eighth of an inch. As depicted, the second ultrasonic beam 40 is emitted along a second beam path 42 parallel to and above the car floor plane 22 by a second vertical offset. An example of a second vertical offset between the first and second beam paths 24 and 42 is an half of an inch. These vertical offsets can vary. Indeed, in an alternate embodiment, the first beam path 24 is parallel to the car floor plane 22 and its vertical offset relative to the car floor plane 22 is zero.

An example of the height adjustment system 20 is shown in FIG. 5. As depicted, the height adjustment system 20 has a housing 44 having a back face 44 a and an opposite front face 44 b. In this specific embodiment, the housing 44 houses the processor 18 in contrast with the embodiment of FIG. 1 where the processor 18 is provided outside the height adjustment system 20. The housing 44 can be watertight and can be made of stainless steel. As shown, the first and second ultrasonic sensors 32 and 38 are mounted to the front face 44 b of the housing 44 and one or more electrical connectors (referred to “the electrical connector” 46) is mounted to the back face 44 a of the housing 44. The electrical connector 46 is connected to the processor 18 which is, in turn, connected to both the first and second ultrasonic sensors 32 and 38. The electrical connector 46 can be provided in the form of a Veam connector. In some embodiments, the back face 44 a can be mounted to the car body via the electrical connector 46. In some other embodiments, the back face 44 a has a mating surface adapted to mate with the car body. In some embodiments, the car body 12 has a corresponding electrical connector configured to removably mate with the electrical connector 46. The car body 12 can also have a recessed cavity to receive at least a portion of the height adjustment system 20 during use. The height adjustment system 20 and the recessed cavity of the car body 12 are designed to allow the first ultrasonic sensor 32 to emit the first ultrasonic beam 34 along the first beam path 24 which can be parallel to but below the car floor plane 22.

In the illustrated embodiment, the housing 44 has three light emitting diodes (referred to as “LEDs 50”) mounted thereto. The LEDs 50 can be useful for troubleshooting the height adjustment system 20. The LEDs 50 can include two green LEDs indicating when the first and second ultrasonic sensors 32 and 38 detect the platform 30 and one red LED indicating when a problem arises.

In alternate embodiments, a pressure value on the hydraulic cylinder(s) 17 can be monitored by a pressure switch in communication with the processor 18. If the pressure value exceeds a certain level, the pressure switch can be operable to disable the communication between the processor 18 and the actuator 15 thus allowing the raising of the car floor plane 22. This can provide a safety measure in case of a failure of the processor 18. The processor 18 can react by illuminating the red one of the LEDs 50.

The red LED can also be illuminated when the processor 18 detects a failure of any of the first and second ultrasonic sensors 32 and 38. In some embodiments, the processor 18 monitors the first and second distance values and, if any one of the first and second ultrasonic sensors 32 and 38 is defective, the processor 18 reads an “out-of-range” value. The processor 18 can also detect a failure if the second ultrasonic sensor 38 provides a second distance value corresponding to the expected distance threshold value 37 while the first ultrasonic sensor 32 does not. Whenever a fault is detected, the processor 18 can be operable to raise the car floor plane 22 and disable the height adjustment system(s) 20. If the failure of any faulty one of the first and second ultrasonic sensors 32 and 38 disappears, the height adjustment system(s) 20 can go back to normal operation.

In cold weather conditions, the first and second ultrasonic sensors 32 and 38 can be blocked by ice and snow. It is thus convenient to provide a heater 52 adjacent the first and second ultrasonic sensors 32 and 38 which can melt ice and snow accumulated on the sensors 32 and 38. The heater 52 can be connected to the processor 18 and even powered by it in some embodiments. The heater 52 can be embodied by resistive wires, for instance. The heater 52 is configured to heat an area surrounding the first and second ultrasonic sensors 32 and 38 to prevent failures associated with ice and snow. The first and second ultrasonic sensors 32 and 38 can be useable even when dirt is present. If the first and second ultrasonic sensors 32 and 38 happen to be covered by mud, the first and second ultrasonic sensors 32 and 38 may stop working properly. However, in this situation, the height adjustment system 20 can go back to normal operation as soon as the mud is cleaned.

To prevent false triggers, the second ultrasonic sensor 38 is debounced during a longer time than the first ultrasonic sensor 32. This longer debouncing can prevent the activation of the hydraulic cylinders 17 caused by a passenger stepping in front of the first and/or second sensors 32 and 38. The first and second ultrasonic sensors 32 and 38 and the processor 18 can be industrial grade so as to sustain vibration, dirt, water, snow, ice, and/or temperatures from 40° C. to 70° C. The first and second ultrasonic sensors 32 and 38 are also designed to withstand car wash.

As shown in FIGS. 3 and 4, the first and second ultrasonic beam sensors 32 and 38 are chosen to have beam angles, relative to the horizon, which prevent interference between one another. For instance, beam angles of below 30°, preferably below 6° and most preferably below 5° have been found to be satisfactory.

An example of an ultrasonic sensor would be those which are installed in car bumpers to assist a car driver when parking. In an embodiment, the ultrasonic sensor will transmit an electrical signal representative of the distance value measured. For instance, a frequency of the electrical signal can increase with a proximity of the object that appears in a line of sight of the ultrasonic sensor.

In alternate embodiments, the first and second ultrasonic sensors 32 and 38 can be configured to emit the first and second ultrasonic beams 34 and 40 obliquely either from below car floor plane 22 or from above car floor plane 22. An ultrasonic sensor which emits an ultrasonic beam obliquely from below the car floor plane 22 can provide shorter distance values whereas an ultrasonic sensor that emits an ultrasonic beam obliquely from above the car floor plane 22 can provide longer distance values.

As can be understood, the examples described above and illustrated are intended to be exemplary only. For instance, the height adjustment performed using the methods and systems described herein can be based on intensities and/or frequencies of the first and second signal values rather than the first and second distance values. In these alternate embodiments, the processor compares the intensities and/or the frequencies of a respective one of the first and second signals to a corresponding threshold value. The processor can be part of a computer having one or more computer-readable memories. In alternate embodiments, the processor is provided in the form of any suitable microcontroller or logic circuit boards. For instance, the processor can receive the electromagnetic signal in a wired electrical connection or in a wireless electrical connection. The scope is indicated by the appended claims. 

What is claimed is:
 1. A method of adjusting a height of a car floor plane of a railroad car relative to a platform of a train station, the method comprising: using a height adjusting system mounted to an exterior side of the railroad car adjacent the car floor plane, emitting a first ultrasonic beam towards the platform of the train station and monitoring a reflection of the first ultrasonic beam; generating a first signal based on said monitoring the reflection of the first ultrasonic beam; and using a processor, operating an actuator of a suspension system of the railroad car to adjust the height of the car floor plane to a height of the platform of the train station based on the generated first signal.
 2. The method of claim 1, wherein said emitting the first ultrasonic beam further comprises emitting the first ultrasonic beam outwardly from the railroad car and parallel to the car floor plane.
 3. The method of claim 1, wherein said emitting the first ultrasonic beam further comprises emitting the first ultrasonic beam parallel to and below the car floor plane, the car floor plane and a first plane of the first ultrasonic beam having a first vertical offset below or equal to an eighth of an inch.
 4. The method of claim 1, wherein the first signal is indicative of a first distance value between the height adjustment system and an object that appears in a line of sight of the first ultrasonic sensor.
 5. The method of claim 4, wherein said adjusting further comprises lowering the height of the car floor plane until the first distance value is equal or smaller than an expected distance threshold value.
 6. The method of claim 1, further comprising, using the height adjustment system, emitting a second ultrasonic beam along a second plane parallel to and above the car floor plane and towards the platform of the train station, monitoring a reflection of the second ultrasonic beam; and generating a second signal based on said monitoring the reflection of the second ultrasonic beam, wherein said adjusting is further based on the second signal.
 7. The method of claim 6, wherein the first and second ultrasonic beams each have a beam angle of below 30°, preferably below 6° and most preferably below 5°.
 8. The method of claim 6, wherein the second signal is indicative of a second distance value between the height adjustment system and an object that appears in a line of sight of the second ultrasonic sensor.
 9. The method of claim 8, wherein said adjusting further comprises increasing the height of the car floor plane when the second distance value is equal or smaller than an expected distance threshold value.
 10. The method of claim 1, wherein said emitting, monitoring, generating and adjusting are performed upon receiving of instructions to adjust the height of the car floor plane.
 11. A height adjustment system to be mounted to an exterior side of a car body of a railroad car, the height adjustment system comprising: a housing having a back face being removably mountable to the exterior side of the car body and an opposite front face; at least one ultrasonic sensor mounted to the front face of the housing, the at least one ultrasonic sensor being configured to emit an ultrasonic beam away from the front face of the housing and outwardly from the car body when the housing is mounted to the exterior side of the car body; and at least one electrical connector mounted to the back face of the housing and electrically connected to the at least one ultrasonic sensor.
 12. The height adjustment system of claim 11, further comprising a processor being enclosed in the housing and in communication with the at least one ultrasonic sensor and the at least one electrical connector.
 13. The height adjustment system of claim 11, further comprising a heater mounted to the front face of the housing.
 14. The height adjustment system of claim 11, wherein the base face is removably mountable to the exterior side of the car body via the at least one electrical connector.
 15. A method of adjusting a height of a car floor plane of a railroad car relative to a platform of a train station, the method comprising: using a height adjusting system mounted to an exterior side of the railroad car adjacent the car floor plane, emitting a first ultrasonic signal towards the platform of the train station; and monitoring a reflection of the first ultrasonic signal against the platform, including generating an electromagnetic signal indicative of whether or not the reflection is detected; and using a processor to receive the electromagnetic signal and operate an actuator of a suspension system of the railroad car to adjust the height of the car floor plane based on the electromagnetic signal received.
 16. The method of claim 15, wherein the step of operating the actuator includes lowering the height of the car floor plane when the reflection is not detected and until the reflection is detected.
 17. The method of claim 15, further comprising emitting a second ultrasonic signal towards the platform of the train station, the second ultrasonic signal being emitted parallel and higher than the first ultrasonic signal, and monitoring the reflection of the second ultrasonic signal; wherein the step of using a processor comprises operating the actuator to raise the height of the car floor plane if the reflection of both the first ultrasonic signal and the second ultrasonic signal are detected. 